If I could go back in time and give my younger self some advice, I'd tell that young boy some things which would change the way he'd live his life. You see, from the vantage point I have now, I know that the world he's going to live in is far different from the one he thinks is ahead. Back there, he was thinking about a world based on romantic notions of progress, potential and possibilities. But what is really around the corner has nothing at all to do with any of those things.
Firstly, I'd tell him that, above all else, money is the most important thing with which he'll ever need to concern himself. Acquiring it, keeping it and increasing it is the holy trinity he should be focused on to the exclusion of all else. Money is power and influence and security and control. Money is a passport to any lifestyle one chooses to live. Money can buy whatever you need in any circumstance. Money paves the way and makes all things possible.
This, of course, means that the very first thing he needs to put aside is any inclination towards the arts. My God, what a colossal waste of time and effort is contained in that pursuit! I would regale him with terrifying tales of years spent pouring physical and emotional fuel into creating piles of useless expression never appreciated by a single soul. I would horrify him with the hopelessness of trying to communicate with a world completely indifferent to every effort. I would crush his hopes by painting a pallid picture of tossing great pearls before a world of porcine ignorance and swine incapable of appreciation or comprehension. No, no, no! First and foremost, forget all about that.
Instead, I would suggest real-estate as one profitable pursuit. Property ownership in the right areas is paramount because when you control property, you control people. But there's also much to be done in the speculation and investment markets. In fact, a good con can move masses into unleashing great gobs of capitol into your disposal. The main point to remember here is that one need not be concerned with legalities or ethics in any way. The acquisition of wealth is its own end and any means to that end is justifiable. The only consideration is that, if you're going to play outside the rules, be smart about it and don't get caught crossing the lines. However, if you do find yourself afoul of the law, be assured that money has its privileges and that "greasing" the right palm can go a long way to avoiding issues.
As for people and relationships, I would counsel to view them as resources and always consider them expendable. Other humans are merely there for your convenience and should be used unflinchingly and thoroughly and, once exhausted of their value, discarded with as little consideration as one would give a piece of soiled tissue. Anyone who would be unwise enough to attempt to thwart your objectives or interfere with your plans should be dispatched as quickly, efficiently and mercilessly as possible. Again, one should endeavor to avoid legal complications, but be cognizant that there are always means by which individuals can be cleanly "eliminated", particularly when the price is right.
Romance is a trap and should be avoided at all costs. Romantic entanglements will only ever compromise your standards and dull your judgement. Indulge your sexual proclivities as freely and frequently as you like, but maintain authority over anyone whom you would involve in such activities and be prepared to dispose of that relationship the instant you detect any attempt to influence your actions or interests. All such efforts by others are a distraction.
The future is only that time in which you expect to live and anything beyond that span is of no concern. Therefore, plan only to secure your own comforts for as long as you can reasonably foresee your survival and no more. What state you leave the world when you die is irrelevant because you won't be around to experience it, so don't worry about it. It's unlikely that you'll leave any heirs behind anyway, so you don't need to make provisions for them or any other descendants.
These are the core values I would impart to my younger self in the hopes that he would avoid the wasted life I have lived. These are the true values of the world he will have to live in. These are the codes driving the most successful people he will encounter in his life. Look around and find a single example of "success" in this world which does not rest atop these very principles. Look no further than the current leader of the free world to find the most perfect expression of these truths in action. Don't tell me that there's another way of living, a "righteous" way where people don't trample all over each other to secure their success. I don't see that world anywhere and I don't see any evidence it will ever manifest.
No, this is what I would tell that boy before he set off on his journey. This is the roadmap I would place in his hands and this is the future for which I would make sure he was prepared.